Currently the only way I can find to have a nationbuilder theme make a secure API call is to hash some auth info about the current user in the template with a secret key. Shopify Liquid and most liquid variants support the hmac_sha256 filter (https://shopify.dev/docs/themes/liquid/reference/filters/string-filters#hmac_sha256) for this purpose, and have for several years. However, sadly this is not available in nationbuilder yet. The only hashing function available in nationbuilder liquid is md5, which is much less secure and isn't a hmac. When will nationbuilder liquid support his important hmac_sha256 filter? I think given how much nationbuilder's users are targets for hackers, it's absolutely essential for nationbuilder to support the hmac_sha256 liquid filter.